I have an issue that I was hoping you could help me with.
I have a central board that takes inputs from the car and controls other boards using I2C. The central board has 3 power inputs:
1)12V When Car Unlocks:
2)12V Live when Ignition Turned:
3)12V Live With Toggle Switch
The central board gives power to 3 other boards.
In total 20A could be drawn.
These are the different scenarios for power:
a) Only 1) on.
b) 1) and 2) on.
c) 1) and 2) and 3) on.
d) 1) and 3) on
e) Only 3) on
Current cannot be shared between the 3 power inputs on the car side. But on the boards, when more than one is available I would like power to be shared evenly.
I am guessing diodes are the right way to go. Does anyone have any suggestions as to what to use? And if so a link to one would be really helpful. The diodes at the moment will just get hot. Preferably I don't want to use a heat sink.